docs: def parameters(names, **kwargs):
      """
      Convenience function for the creation of multiple parameters. For more
      control, consider using ``symbols(names, cls=Parameter, **kwargs)`` directly.
  
      The `Parameter` attributes `value`, `min`, `max` and `fixed` can also be provided
      directly. If given as a single value, the same value will be set for all
      `Parameter`'s. When a sequence, it must be of the same length as the number of
      parameters created.
  
      Example::
          x1, x2 = parameters('x1, x2', value=[2.0, 1.3], min=0.0)
  
      :param names: string of parameter names.
          Example: a, b = parameters('a, b')
      :param kwargs: kwargs to be passed onto :func:`sympy.core.symbol.symbols`.
          `value`, `min` and `max` will be handled separately if they are sequences.
      :return: iterable of :class:`symfit.core.argument.Parameter` objects
      """
      sequence_fields = ['value', 'min', 'max', 'fixed']
      sequences = {}
      for attr in sequence_fields:
          try:
              iter(kwargs[attr])
          except (TypeError, KeyError):
              # Not iterable or not provided
              pass
          else:
              sequences[attr] = kwargs.pop(attr)
  
      if 'min' in sequences and 'max' in sequences:
          for min, max in zip(sequences['min'], sequences['max']):
              if min > max:
                  raise ValueError('The value of `min` should be less than or'
                                   ' equal to the value of `max`.')
  
      params = symbols(names, cls=Parameter, seq=True, **kwargs)
      for key, values in sequences.items():
          try:
              assert len(values) == len(params)
          except AssertionError:
              raise ValueError(
                  '`len` of keyword-argument `{}` does not match the number of '
                  '`Parameter`s created.'.format(attr)
              )
          except TypeError:
              # Iterator do not have a `len` but are allowed.
              pass
          finally:
              for param, value in zip(params, values):
                  setattr(param, key, value)
      return params